Fanha (ファウナッハ) is a secondary antagonist in the 1993 Super Famicom action RPG "Secret of Mana", aka. "Seiken Densetsu 2" (聖剣伝説2) by developer Squaresoft.
She, along with Geshtar, Sheex, and Thanatos, is one of the four minions of the evil Emperor Vandole. She ends up assassinating the Emperor after conspiring with Thanatos so that they can obtain the Mana Fortress, which is capable of world domination.
Fanha's walking sprite.
When cornered, Fanha transforms into a monstrous snake woman called "Lamia-naga" (Hexas in the English version) in order to battle the hero party. After losing, she flees to Thanatos for help, only for him to fatally betray her as well.
Fanha's post-transformation battle sprite
Hexas in the HD remake.
Concept art from the HD remake.